A variety of devices and methods have been used to control the number of common houseflies and other flying insects. Among these are chemical sprays, evaporating insecticides, strips for capturing flies and other insects by means of an exposed adhesive, and electrocution devices. Each of these devices and methods has certain advantages and drawbacks.
For example, electrocution devices are deemed undesirable because of the noise that they cause when a spark is discharged to kill an insect passing between two oppositely charged electrodes. Furthermore, such devices often are covered with partially-dried dead insects, which is unsightly and a problem to clean. Also, such devices may be dangerous because of the high voltage required to electrocute the insects.
Examples of devices for electrocuting insects include the disclosures of the following patent documents:
______________________________________ U.S. Pat. No. 3,935,662 U.S. Pat. No. 4,275,523 U.S. Pat. No. 3,894,351 U.S. Pat. No. 4,037,351 U.S. Pat. No. 4,109,408 U.S. Pat. No. 2,881,563 U.K. Spec. 1,444,089 France 2,411,563 German Offenlegungsschrift 1,607,361. ______________________________________
Many of the electrocution devices also include a bright light or other insect-attracting device. Such devices draw the insects into what is believed to be essentially inadvertent contact or near contact with oppositely charged electrodes. Such contact or near contact bridges or nearly bridges the gap between the oppositely charged electrodes causing a spark to jump the gap by passing through the insect.
Another type of electrical device for killing insects stuns the insect causing it to fall into a receptacle of some kind. Examples of such devices are those disclosed in the following patent documents:
______________________________________ U.S. Pat. No. 4,423,564 U.S. Pat. No. 2,307,163 U.S. Pat. No. 2,038,495 Russia 547,201. ______________________________________
Such devices relate to the trapping and killing of crawling insects and are not concerned with control of flying insects.
Fly strips of the type having adhesive to trap flies or other alighting insects are messy to handle, both before and after insects have been trapped thereon. Furthermore, such strips are often very unsightly.
While insecticide sprays are very effective, some people do not want to spray in certain rooms. Evaporating chemicals which fill a space with insecticide vapors are sometimes thought to produce undesirable odors.
In short, there is a need for an improved device to control the number of houseflies and other flying insects in a room or other space. There is a need for an effective, silent, non-messy and safe device to eliminate flying insects.